The Multiverse In Greek Cosmology

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The Multiverse In Greek Cosmology</h4>

Our scientific understanding of nature is limited to one universe, the observable one, which makes up everything we can see in the cosmos surrounding us. In recent decades, though, experts have wondered if we could extend our scientific theories past this reality, and explore the possibility of a multiverse beyond the stars. And, despite this seeming like a modern concept, it dates back centuries, and even thousands of years. 

This is Unveiled, and today we’re taking a closer look at what Ancient Greek cosmologists knew about the multiverse? 

Greece is undoubtedly one of the cradles of civilization. It’s a region that humans have lived in since as early as the Paleolithic era, otherwise known as the Old Stone Age, which started 3.3 million years ago, running all the way up to roughly the end of the last ice age. Agricultural societies developed on the land in and around Greece from about 7,000 BCE, turning the area into a hotspot for Bronze Age civilizations. This all came to a harsh end during the Late Bronze Age collapse, however, which happened in roughly the 12th century BCE. The reasons why aren’t exactly clear, but it was around this time that Greece entered into a three century-long dark age. It was a period of struggle, but it came to an end. And ultimately, what the world now chiefly thinks of as Ancient Greece emerged and began to flourish, becoming the dominant Mediterranean culture during the time of antiquity. 

The power of Greece perhaps peaked under the rule of Alexander the Great, whose empire completely transformed the world at the time. But, after his death, in-fighting broke out, and Greece endured some of its most tumultuous years. Soon came the Roman conquest of Greece, and while the historic lands would continue to blossom under Roman rule, the wheel of history had turned. Nevertheless, Greece had had a huge and lasting impact on the human story. For many, it is the birthplace of modern civilization.

What’s not tied together quite so often, however, is the Ancient Greeks and the multiverse. But, actually, there's a good argument to say that the idea of the multiverse was born in Greece. So, how do we get there?

In the earliest Greek myths, the cosmos emerged from Chaos, an undefined, primordial state. Chaos perhaps mirrors our modern concept of reality before the Big Bang, when all matter was confined to a singularity of infinite density. For the Greeks, however, it was from Chaos that the first deities emerged, in particular Gaia and Ouranos - the Earth and Sky gods. Along with a select few other gods, they shaped the universe into an ordered system. The concept of Chaos evolving into structure is a central theme in Greek cosmology, and still a popular viewpoint in the modern day - even if contemporary explanations are usually less divine in nature. Because of the inherent unknowableness of Chaos, though, it’s little wonder that some started to push for further, more rational explanations.

The iconic philosopher Anaximander was one of the first. He claimed reality was more specifically born from the Apeiron, an infinite, boundless substance. The Apeiron was the origin of all things, an abstract concept that sought to make sense of the underlying mechanics of reality. The problem was that Anaximander’s boundless realm actually wasn’t all that specific at all, and so it never really caught on. But the search for something other than Chaos had begun.

The next great shift came with Empedocles, a century after Anaximander, who established the four classical elements - earth, air, fire, and water. They were considered to be the building blocks of existence, constantly interacting to form the material world. Empedocles’ view is in many ways reflective of modern chemistry, albeit with far fewer elements to play with. Elsewhere, and the Greeks also believed (in general) in a structured, hierarchical solar system. Ptolemy popularized this geocentric model, with a fixed Earth at the center, and it went on to dominate cosmology for centuries.

All these ideas combined to form the basis of our modern, mainstream understanding of the universe. This isn’t (and wasn’t) where Greek cosmology ends, though. Some did go further, and proposed a theory that included the possibility of multiple worlds. The Atomists - chiefly Leucippus and his disciple Democritus - were some of the most influential in this field. As the name of their school implies, they pioneered the concept of the atom. Their ideas, which were radical at the time, said that everything in the universe was made up of tiny, indivisible particles. These particles, the atoms, then moved through an infinite void, combining in countless ways, to form various objects, beings, and all the phenomena of reality. 

Crucially, though, from the atomist’s perspective, there was no one, singular, unique universe. Instead, Leucippus, Democritus and their followers believed that the vastness of the void, and the limitless nature of atoms, should lead to infinite worlds. The nature of these alternate realities varied, with some mimicking our own, and others appearing completely different. The worlds could vary in size, composition, and presence of life. Some might be deemed physically better for life than ours, others would be physically worse. All manner of combinations and conditions were possible. Again, this was groundbreaking at the time. It was a theory of infinite worlds in constant flux, and it challenged the overriding Ptolemaic notion of a singular, ordered universe, centered around the Earth. Interestingly, though, it was first laid out centuries before Ptolemy was even alive. The atomists were seemingly far, far ahead of the curve. They were challenging the status quo before the status quo had even been set.

Epicurus was another key Atomist figure. He lived in the early Hellenistic period, during the era that immediately followed the death of Alexander the Great. He founded his own school in Athens, where he continued teaching atomism for a new generation, in the third century BCE. Among other things, Epicurus asserted that because atoms moved randomly, colliding in various ways, the formation of multiple worlds was not only possible - but inevitable. This idea of spontaneous creation fueled much of the Epicurean worldview, but it also closely parallels even the most modern concepts of a multiverse. Alongside this universe there are others, and endlessly so. 

Importantly, while Epicurus wasn’t alone, views like his still weren’t the norm. As today, talk of multiple worlds was met with suspicion and skepticism by many of his contemporaries. Most believed in a finite and closed universe, but we can see that the seeds were being sown for something more. And, ultimately, perhaps the emerging shoots of this new idea were most famously discussed a few years before Epicurus. Anxarchus was another famous atomist, a generation before Epicurus’ time, and noteworthy for his travels with Alexander the Great. One interaction between him and Alexander went down in history, when Anaxarchus is said to have told the great king that there were many worlds beyond our own. Upon hearing this, it’s then said that Alexander wept, crestfallen to realize that even though there were many worlds, he had yet to fully conquer even one. It’s one of the most famous chapters in atomist history and, as well as demonstrating just how huge the ego of Alexander must have been, it reveals just how ancient and embedded belief in the multiverse really is.

Unsurprisingly, and famously, there were always other worldviews along the horizon of Ancient Greek thought. Notably, Stoicism emerged to rival Atomism. Stoic cosmology instead proposed a cyclic universe, an idea that followers called eternal recurrence. It suggests that the cosmos will experience a continued cycle of birth and destruction, repeating forever. Clearly there are modern comparisons to be made here, as well, including in relation to the Big Crunch and Big Bounce alternatives to the Big Bang Theory. But the many worlds of an atomist inclination were never disproven or discarded. Lucretius, for example, was a Roman poet and Epicurean philosopher, who lived in the first century BCE. And one of his poems, “On the Nature of Things”, describes a universe teeming with endless worlds, all shaped by the chaotic movement of atoms. 

With today’s research, our greater understanding of science fact, and our wide variety of science fiction, it can all feel like the multiverse is an entirely new and exciting phenomenon. But clearly it isn’t, and our greatest minds have long pondered the possibility of other worlds and realms somewhere distant from here.